Common faults and maintenance methods of air conditioner

Common faults and maintenance methods of air conditioner

Fault 1: Water leakage

There are several reasons why the indoor unit of the air conditioner leaks:

1、Improper installation of the body:

The indoor unit is inclined, and the direction of the pipe port is too high.

2、The drainage pipe is bad:

Poor drainage due to slack or bent drain pipes in a wavy shape.

3、 Dew condensation on the piping:

Because the insulation material on the pipe is too poor or too thin, when the refrigerant in the pipe passes through, it will cause condensation.

4.、Water dripping from the outdoor heat exchanger:

1) The heat exchanger is covered with dust, causing the temperature of heat exchange to be uneven, and water droplets are generated in the middle of the heat exchanger, and the water droplets that fall outside the water receiving tray will drip into the room.

2) Insufficient refrigerant in the air-conditioning system causes the indoor unit to freeze, and the water droplets formed by the melting of the ice do not drop directly into the water receiving tray.


Fault 2: Fluorine leakage

We can check whether the air conditioner leaks fluorine through the following 4 small methods:

1. "By hand" Touch the condensing louver fan behind the air conditioner with your hand. If the temperature is not cool or hot, and the compressor is still working, it means that fluorine has run out.

2. "By eyes" In the cooling state, adjust the temperature controller so that the set temperature is 6°C to 8°C lower than the room temperature. After running for 15 minutes, check the indoor unit hydraulic pipe (that is, the thin copper pipe), there should be no Frosting phenomenon, otherwise, the machine has fluorine leakage failure. Whether there is any oil stain on the copper pipe connector, if there is oil stain, it also indicates that there is fluorine leakage.

3. "By ears" If you find that the compressor has been working since it was turned on, there is no vibration from shutdown, and the sound of the compressor's self-vibration is louder than when it was newly purchased, it may be an abnormal sound caused by fluorine leakage.

4. "Temperature measurement" Find a thermometer, close to the cold air outlet, and see if the temperature indication is 6°C to 8°C lower than the room temperature. Prove that the fluorine has run away.


Fault 3: No heating

1. Improper use

The air conditioner does not clean the filter in time after a long period of time, and the air circulation is blocked inside, which will affect the heating effect of the air conditioner to a certain extent.

Too thick dirt on the evaporator and condenser will also reduce the heat exchange effect, resulting in a decrease in heating capacity and an increase in power consumption; the heating temperature is set too low.

The air-conditioning room door cracks, wall holes are not blocked, or the windows are opened frequently, resulting in the loss of indoor heat, etc., which will inadvertently cause the air-conditioning heating to be weak.

2. Environmental factors

Heating and cooling air conditioners are divided into three types: heat pump type, heat pump auxiliary electric heating type and electric heating type. Under the condition of equal heating capacity, the power consumption of the first two types is about half less than that of the third type. Considering the power supply capacity and electricity costs, the current family The first two types of air conditioners are generally selected (but attention should be paid to their use conditions, the first two are usually only applicable to environments above -5°C, obviously not applicable to colder areas).

For heat pump air conditioners,if the ambient temperature is too low during heating, and the energy efficiency ratio of the air conditioner is also reduced. And if the heat pump air conditioners has no automatic defrosting, the minimum ambient temperature used is -5°C , and no heating is performed below this temperature. or very ineffective. This is because the frost on the external heat exchanger blocks the air flow and can no longer absorb heat from the outside. For heat pump air conditioners with automatic defrosting, lower than his minimum ambient temperature cannot effectively heat. At present, the lowest temperature of the heat pump air conditioner of Inverboost technology can support -12 ℃, which can achieve a greater degree of practicability for colder areas.

3. Failure of refrigeration cycle system and control system

1) Insufficient refrigerant.

If the refrigerant leaks or is caused by insufficient reasons, you can simply perform a self-test to identify whether there is leakage of fluorine.

2) The four-way valve is connected to the air.

Heat pump air conditioners switch between cooling and heating states through a four-way valve. If the four-way valve is connected to the air, some of the refrigerant that should be involved in heat exchange will be directly returned to the return pipe from the compressor outlet pipe at the four-way valve, resulting in the reduction of the refrigerant participating in the heat exchange and the decrease in the heat exchange efficiency, thus causing Insufficient heating capacity.

3) The one-way valve (also known as the check valve) is leaking.

When the one-way valve leaks, the pressure difference between the high and low pressures of the refrigeration system drops, the temperature of the outdoor heat exchanger rises, and the heat obtained from the outside decreases, resulting in insufficient heating. When the air-conditioning refrigeration is normal and the heating capacity is insufficient, by detecting the pressure of the system during operation, it will be found that the pressure on the low-pressure side rises and the pressure difference between the high and low pressure drops.




4) The defrost controller fails.

When the heat pump air conditioner is in the heating state, the evaporator is located in the outdoor unit. For the heat pump air conditioner using the thermal flushing and defrosting device, if the defrost controller fails, so that the air conditioner cannot switch to the defrosting operation state in time, there will be a problem. When the heat pump is heating, the evaporator is frosted, which affects the heat exchange efficiency of the air conditioner heating, resulting in insufficient heating capacity or even shutdown.

At this time, it should be observed whether there are the following phenomena: the defrost temperature sensing device is dislocated, the contact is sticky or poor, the fan impeller is slipping or the air duct is blocked, and the solenoid valve or starting relay is invalid.

5) The auxiliary electric heating function fails.

Now the heat pump auxiliary electric heating type air conditioner generally adopts the PTC electric auxiliary heating technology. The PTC electric auxiliary heating technology can quickly heat up under ultra-low temperature conditions, with strong efficiency, safety and reliability, and can be used for a long time. If the electric auxiliary heating control circuit or electric auxiliary heating equipment fails and cannot work normally, when the ambient temperature is relatively low, the air conditioner will be insufficient for heating, or even the air conditioner will not heat at all when the environment is harsh.


For heat pump-assisted electric heating type air conditioners, if the ambient temperature is high (above 5°C) and the heating is normal, but the ambient temperature is low (below 0°C), the heating capacity is insufficient or no heating, the electric auxiliary heating control circuit should be suspected. Or the electric auxiliary heating equipment fails, and the maintenance should focus on checking these two parts


More Posts